1. Field of the Invention
The present disclosure relates to a semiconductor device, liquid discharge head, liquid discharge cartridge, and liquid discharge apparatus.
2. Description of the Related Art
A liquid discharge head for discharging a liquid from an orifice is used as an inkjet printing head by using ink or the like as a liquid, and depositing the ink on a print medium such as paper by controlling the discharge of the ink in accordance with a print signal. Also, a liquid discharge apparatus including this liquid discharge head is applied as, for example, an inkjet printing apparatus. An inkjet printing head using thermal energy selectively generates a bubble in a liquid by applying thermal energy generated by a heater to the liquid, and discharges an ink droplet from an orifice by the energy for generating a bubble. Recently, the number of orifices has been increased in order to increase the speed of printing. On the other hand, variations in resistance value from a bonding pad portion to each heater increase, and this makes it difficult to evenly supply electric power to a plurality of heaters. As a measure to cope with this problem, FIG. 5 of Japanese Patent Laid-Open No. 2005-104142 shows an arrangement in which an electrically conductive line for supplying electric power to a heater is divided into a plurality of electrically conductive lines, thereby reducing variations in resistance value of each electrically conductive line. Referring to FIG. 5, four heaters 101, four power transistors 102, and four logic circuits 103 form one segment (unit circuit). Variations in resistance value of a VH line to each segment are reduced by increasing the line width of a VH line connected to a segment positioned far from a bonding pad portion. This applies to a GNDH line from the bonding pad portion to each segment.
When the printing head disclosed in Japanese Patent Laid-Open No. 2005-104142 is made longer by increasing the number of heaters arranged on a semiconductor substrate, the number of divided electrically conductive lines connected to power supply pads increases. Since the line width from the bonding pad portion to each segment cumulatively increases, an area necessary for a wiring layout expands, and the size of the printing head increases. To solve this problem, Japanese Patent Laid-Open No. 2011-245801 proposes a wiring layout for suppressing the expansion of the wiring area.